Curtain Fabric Calculator.
Estimate how much fabric to buy for a single curtain or pair using your actual track width, finished drop, fabric width and chosen fullness.
Curtain measurements
Calculate fabric length from your actual pole, drop, fabric width and chosen fullness.
Use the fullness specified for your heading style or your own preference.
Pattern repeat & sewing allowance
Add only the allowance required by your chosen heading and hem construction.
Leave blank for plain fabric or when pattern matching is not required.
Fabric required
Enter your curtain and fabric measurements to calculate metres and yards.
No fullness, hem or pattern allowance is assumed for you. Use the values required by your heading style, fabric and sewing method.
From curtain fullness to fabric widths
The required finished curtain width is the track or pole width multiplied by the fullness you choose. That width is divided by the usable fabric width and rounded up to whole fabric widths. For a pair, an odd number of widths is rounded up again so both curtains can use the same number of drops.
Each drop uses the finished curtain length plus any heading and hem allowance you enter. The calculator then multiplies the cut length by the number of drops and converts the result to both metres and yards.
Pattern repeat is handled separately
If you enter a vertical pattern repeat, each cut length is rounded up to the next full repeat. That provides the extra length needed for repeat alignment without pretending that every fabric needs the same matching allowance.
Frequently asked questions
How do I calculate how much curtain fabric I need?
Enter the pole or track width, finished drop, fabric width and your chosen fullness. The calculator determines the number of fabric widths and total length in metres and yards.
Why does a pair sometimes need an extra fabric width?
A curtain pair normally needs the same number of fabric widths on each side. If the first calculation produces an odd number, the tool rounds up to the next even number.
What should I enter for fullness?
Use the fullness recommended for your heading style or the fullness you have chosen. The calculator does not impose a universal fullness value.
How does pattern repeat change the fabric amount?
When a vertical repeat is entered, each cut length is rounded up to a whole repeat so the repeated design can be aligned between fabric widths.